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how can i modify the circuit by replacing the LED and photo diode by using ultrasonic sensor? Answered

please for any one who is capable of drawing a schematic diagram on how i can modify, and use ultrasonic sensor  as a transmitter and receiver for my circuit to work well. also i want it to operate without using micro-controller. 


Which ultrasonic sensor?

This is how you would wire up this one.


thank you for your advice, and i need you to assist me in producing a circuit on a verobord since i have tried several experiments on it but i failed to obtain a proper result.

Did you build it in a circuit simulator program or on a bread board?

Some circuit simulator programs do not do well with negative logic.

Try adding a general purpose NPN transistor like a 2N3904 or a BC547. Connect the transistor base to the green wire, the emitter to the ground, and the collector to the - of the Opamp


Excellent and works very well. BUT this would work as though something is blocking the old LED.. You have to place a sound reflector within 24' sonic range, to light the D5 LED and close the relay..

While mine is active LED with no reflector the D5 LED is on while the relay is closed and placing a sound reflect card will open the relay and off the LED...

thank you for your patronage you have helped me a lot

Wouldn't that at least require some modulation to check for a signal?
The way I understand them you need some electronics as otherwise they won't do a thing except create noise.
And if that works then I guess everything in the right frequency range will trigger it, so don't break glass or have bats around ;)

The units I have experience with are able to beep (enunciate) with a simple 5 volt supply..

True most are simple piezo discs that require an oscillator...

The photo diode basically acts like a switch in your shematics.
So in the most basic form you could replace it with an ultrasonic module that has a relay in it.
Of course you can replace the relay with a transistor.
Once the receicer is active it does the same as the photo diode: It provides a path for pin 2 of IC2A to ground.

Not quite sure what the stuff does as I don't know the IC's used but I guess you are only after activating it by ultrasonic instead of light...